James bishop



(No Model.)

J. BISHOP.

PAPER PULP SCREEN. No. 581,671.Y Patented Apr. 27, 1897.

IIIIII ull rrn Srarns ArNr Ormeso JAMES BISHOP, OF HULL, CANADA,ASSIGNOR OF ONE-HALF TO JOHN PAINTER, OF SAME PLACE.

PAPER-PULP SCREEN.

SPECIFICATION forming part of Letters Patent No. 581,671, dated April27, 1897. Application iiled December 9, 1896. Serial No. 615,071. (Nomodel.)

To all whom t may concern.-

Beit known that I, J AMES BISHOP, of Hull,-

in the Province of Quebec, in the Dominion of Oanada,have inventedcertain new and useful Improvements in Paper-Pulp Screens; and I dohereby declare that the following is a full, clear, and exactdescription of the same, reference being had to the accompanyingdrawings, in Which- Figure l is a top view of my pulp-screen, the screenpartly broken away to show the inclined divisions in the trough; Fig.2,a side elevation of the same; and Fig. 3, a section on line X X, Fig. l,the screen shown as entire.

My invention has for its object to prevent the meshes or perforations ina paper-pulp screen from becoming clogged with pulp by passage of airthrough one-half the meshes in alternate and opposite directions, andalso to prevent the accumulation of cstrings of solidified pulp hangingfrom the bottom of the screen, which, dropping into the vat, do notamalgamate with the semifluid pulp, but cause irregularit7 and breaks inthe paper when the pulp is made into paper.

My invention consists of a bottomless trough divided by one or morevertical longitudinal partitions and inclined transverse partitions, thealternate rows of spaces formed by the divisions inclining in oppositedirections, a screen within said trough and above said divisions, andmeans for reciprocally agitating the trough, so that when moving in onedirection the correspondingly-inclined series of divisions will forcethe air upward through the meshes and the reversely-in clined series ofdivisions will suck through the meshes above them, and when the troughmoves in the opposite direction a vice-versa air action through thescreen-meshes is produced.

A is the vat, which receives the screened pulp, and A an opening in theside to remove the pulp.

B is a bottomless trough mounted partly within and partly above the vat,preferably by a spring O at each end, the ends of the springs thickenedto rest in bearings D, secured to the corner-posts E, which support thevat, so that the trough can be shaken reciprocally in a short tremulousmotion by suitable mechanism. l

The trough B is divided longitudinally by one or more verticalpartitions B and subdivided by transverse partitions B2. One half of thenumber of said partitions B2 incline in one direction and the other halfin the opposite direction, said partitions and divisional spaces formingan open bottom to the otherwise bottomless trough.

F is a screen lying on the partitions, and through the meshes orperforations of said screen the pulp passes into the vat below when thetrough is agit-ated reciprocally.

The trough is reciprocated by anysuitable mechanical means, preferablyby pitmen K K, one at opposite sides, connected to ecceir tries L L on ashaft P, journaled in bearings supported by the end posts E and carryinga cone-pulley M. A cone-pulley N is jour-v naled below the same andcarriesa iiy-wheel R, and said pulleys are connected by a belt Q foradjusting the speed.

The trough above the screen is iilled with the semiliquid pulp to bescreened and the trough agitated reciprocally. When the trough moves inone direction,the air in spaces G, which incline in that direction, willmove upward and clear the perforations or meshes covering saiddivisional spaces, and the other divisional spaces, II, will causesuction through the perforations or meshes above them and prevent theformation of strings of solidified pulp accumulating on the bottom ofthe screen and dropping into the vat, to the injury of the paper whenmade.

Then the trough is reciprocated in the opposite direction, thedivisional spaces G Will suck and the divisional spaces H blow throughthe meshes of the screen. The sucking spaces become blow-spaces at thereturn motion of the trough.

The trough may be divided into inclined divisional spaces by anypreferred arrangement of partitions, and I do not limit myself to theseries shown and described herein.

I claim as my inventionl. A paperpulp strainer, comprising a bottomlesstrough divided by a vertical longitudinal partition B', and transversepartitions IOC B2, on opposite sides thereof, the partitions on one sideof the longitudinal partition slo'ping in an opposite direction to thepartitions on the other side, a screen F, covering the divisional spacesWithin the trough, and means for reciprocating the trough longitudinallyin a horizontal plane, as set forth.

2. A paper-pulp Strainer having a bottoniless trough divided bypartitions into rows of spaces sloping in opposite directionslongitudinally of the trough, said rows separated by a verticalpartition, a screen covering the divisional spaces, a vat below saidtrough, and means for reciprocating the trough in a horizontal planerelatively to the sloping spaces, as set forth.

3. In a pulp-strainer, the combination of a vat to receive the screenedpulp, a bottomless trough divided by partitions sloping in oppositedirections, a sieve or screen covering the divisional spaces, and meansfor reciprocating the troughin a horizontal plane relatively to thedirection of the slope of the partitions, substantially as set forth.

JAMES BISHOP. lVitnesses:

HENRY GRIsT, JOHN GRIsT.

